An alternative route to existing silicon on insulator (SOI) material technologies such as SIMOX (separation by implanted oxygen) and BESOI (bonded and etch-back SOI) is the new Smart-Cut process, which appears to be a good candidate to achieve ULSI criteria. The Smart-Cut process involves two technologies: wafer bonding and ion implantation associated with a temperature treatment which induces a in-depth splitting of the implanted wafer. The details of the Smart-Cut process, the physical phenomena involved in the different technological steps such as hydrogen implantation related mechanisms and wafer bonding are discussed. The characteristics of the final structure in terms of thickness homogeneity, crystalline defects, surface microroughness, and electrical characterization are presented. Other applications of this process are also highlighted.